Roof having improved base sheet using metal/fabric layers with overhangs

ABSTRACT

A roofing panel includes an insulation board and a laminate of a metal layer and a fabric layer attached to the board. The board has a quadrilateral shape defining four edges and the laminate is attached to the board such that the laminate overhangs at least two of the edges of the board. A roof is formed from a plurality of the roofing panels which are interconnected with one another such that an overhanging edge of one roofing panel overlies a non-overhanging edge of an adjacent roofing panel.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority to ProvisionalApplication Ser. No. 60/529,379, filed Dec. 11, 2003 and entitled“ROOFING PANELS HAVING METAL/FABRIC LAYER LAMINATED TO INSULATION BOARDWITH OVERHANGS,” the entire disclosure of which is incorporated herebyby reference.

BACKGROUND OF THE INVENTION

The present invention relates generally to roofs and, more particularly,to a metal/fabric laminated roofing panel and to roofs made using thesame.

Although the present invention is applicable to any type of roof, it hasparticular applicability in connection with its use in built-up andsingle ply roofs.

Built-up roofs are formed of alternate layers of bituminous material andfelt which are assembled or “built-up” in the field. The alternatelayers of bituminous material and felt are assembled onto a base sheetwhich overlies an insulation layer. The insulation layer and base sheetare attached to a roof deck which typically is made of metal, wood,concrete gypsum or any other conventional deck material.

The term “built-up roof composite” as used herein means any one of aplurality of different conventional built-up roof composites used on thetop of base sheets, such as the built-up roof composite describedherein, as well as others, such as EPDM, PVC, modified bitumen, coal tarand Hypolon.

The bituminous material is usually of coal tar or asphalt origin and isapplied by hot-mopping between alternate layers of the felt.

The primary function of the base sheet is to prevent blistering ofoverlying layers. Additionally, the base sheet prevents the bituminousmaterial from dripping into and through the deck. Such penetration has anumber of disadvantages. First, any dripping during installation canpenetrate into the underlying building, thereby causing injury to peopleand damage to equipment, furnishings, etc. Additionally, dripping, inthe case where the underlying deck is made of wood, could also serve toattach the insulation layer to the deck by means of the bituminousmaterial, as well as the mechanical fasteners, thereby making removal ofthe insulation layer difficult in those situations where it is necessaryto replace the roof. Further, the overlay prevents any of the overlyingbitumen from passing through the deck and into any interior fire,thereby preventing any further fueling of the fire.

An alternative structure to the built-up roof is a weather resistantelasto-plastic membrane which may comprise, for example reinforcedpolyvinyl floride, butyl rubber, vinylidene chlorides and fluorides,polyesters, polyvinyl chloride, neoprene, chlorosulfonated polyethylene,polysulfides, polyurethanes, polyepoxies, acrylates, and other materialshaving suitable mechanical strength and weather durability. Suchstructures are generally designated “single-ply roofs” because a singlethickness of the weather-resistant membrane is generally sufficient, ascompared with the plurality of layers of roofing felt generally requiredfor built-up roofs. In addition to the membrane, a layer of insulatingmaterial is also generally provided between the membrane and the roofdeck of the structure in single-ply roofs.

The term “roof covering” as used herein means either a built-up roofcomposite or a single ply membrane.

An improved base sheet which provides superior fire resistance and winduplift prevention compared to prior art base sheets is disclosed in U.S.Pat. Nos. 6,108,993 and 5,884,446, the entire disclosures of which areincorporated herein by reference. As disclosed in U.S. Pat. Nos.6,108,993 and 5,884,446, the base sheet includes a laminate comprised ofmetal, such as aluminum, and a fabric, such as non-woven polyester.

In the case of a built-up roof, the metal layer serves as a fire barrierto prevent bitumen entering the underlying building and fueling a fire.Additionally, the metal layer acts as a barrier for preventing anybitumen (or other material) applied during installation from penetratingthe deck and into the interior of the underlying building. Additionally,the metal layer, in the case of wood decks, prevents the roof from beingadhesively attached to the deck since such adhesion could make roofreplacement very costly and, in some cases, impossible.

Additionally, a roof using the base sheet of U.S. Pat. Nos. 6,108,993and 5,884,446 requires fewer mechanical fasteners to achieve superiorwind uplift prevention. Less fasteners results in a substantialreduction in material and installation costs.

The metal layer also acts as a barrier to moisture vapor resulting fromhigh humidity conditions in the underlying building. Moisture vaporpassing into a roof could cause blistering, cracking and distortion ofthe roof. The metal layer prevents such moisture from reaching any ofthe overlying layers. In order to prevent the moisture vapor trapped bythe metal vapor barrier from being trapped in the insulation layer andcausing damage or lack of effectiveness thereof, it is necessary to ventsuch moisture vapor.

To this end, in accordance with one aspect of the invention disclosed inU.S. Pat. Nos. 6,108,993 and 5,884,446, the metal layer has embossmentsthereon which form channels to the edge of the roof, thereby venting anyentrapped vapors.

SUMMARY OF THE INVENTION

The present invention is directed to a roofing panel employing the basesheet disclosed in U.S. Pat. Nos. 6,108,993 and 5,884,446.

In accordance with an embodiment of the invention, the roofing panelincludes an insulation board having a quadrilateral shape defining fouredges and a laminate of a metal layer and a fabric layer attached to theboard such that the laminate overhangs at least two of the edges of theboard.

In accordance with another embodiment of the invention, a roof comprisesa plurality of the roofing panels which are interconnected with oneanother such that an overhanging edge of one roofing panel overlies anon-overhanging edge of an adjacent roofing panel.

Other features and advantages of the present invention will becomeapparent from the following description of the invention which refers tothe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a roofing panel in accordance with anembodiment of the present invention.

FIG. 2 is a sectional view taken along the lines 2-2 of FIG. 1.

FIG. 3 is a sectional view of an alternative embodiment of a roofingpanel in accordance with the present invention.

FIG. 4 is a plan view of a roof employing a plurality of roofing panelsin accordance with certain features of the present invention.

FIG. 5 is a plan view of a panel having different indicia for thelocation of fasteners.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Referring now to the drawings and, particularly, to FIGS. 1 and 2, thereis shown an embodiment of a roofing panel 10 illustrating certainfeatures of the present invention. The roofing panel 10 includes alaminate 12 of metal 14 and fabric 16. Preferably, the metal 14 isaluminum and may be 2 mils thick and the fabric 16 is a non-wovenpolyester having a weight ranging from 4 to 14 ounces per square yard. Apolyester sheet having satisfactory properties is one made by the JohnsManville Company, South Carolina and sold under the trade name ofTrivera®. A suitable aluminum/polyester laminate is Polaralume®,marketed by Palisades Atlantic inc., Ridgefield Park, N.J.

The laminate 12 is attached to a roofing insulation board 18 of any sizesuch that at least two sides, e.g. 12 a and 12 b, overhang the board 18with the other sides 12 c and 12 d cut even to the insulating board 18.The laminate 12 may be attached to the board 18 with the aluminum side14 down, as shown in FIGS. 1 and 2, or with the fabric side 16 down, asshown in FIG. 3. In either case, when the panels 10 are applied to aroofing deck, the laminate will overlap the preceding side.

Referring now to FIG. 4, there is shown an embodiment of a roof 20illustrating certain features of the present invention. The roof 20includes a plurality of roofing panels 10 which are attached to a roofdeck 22 such that an overhanging side e.g. 12 a or 12 b of a panel 10overlaps the non-overhanging side 12 c or 12 d of an adjacent panel 10.The deck 22 may be made of metal, wood, concrete, gypsum or any otherconventional deck material.

The panels 10 are attached to the deck 22 by suitable mechanicalfasteners 24, such as screws or nails, which are inserted throughrespective metal plates (not shown). In accordance with the presentinvention, fewer such fasteners are necessary to attach the panels 10 tothe metal deck 22 to achieve a given wind-up lift prevention as comparedto prior art built-up roofs not using panels or the base sheet disclosedin U.S. Pat. Nos. 6,108,993 and 5,884,446.

Over the overlapping panels 10 a conventional roof covering 26 which maybe either a built-up roof composite or a single ply membrane is formed.

Typically, as discussed above, built-up roof composites are formed ofalternate layers of bituminous material and felt. The felts may befiberglass or may be organic felt, such as asphalt saturated felt or, asdisclosed in U.S. Pat. Nos. 4,521,478, 4,599,258 and 4,837,095, theentire disclosures of which are incorporated by reference, the built-uproof composite may be formed of alternate layers of a non-wovenpolyester and bituminous material. Typically, the bituminous material isusually of coal tar or asphalt origin and is applied by hot-mopping. Themetal layer 14 acts as a barrier to prevent the bituminous material frompenetrating down to the underlying insulation board 18.

One of the problems with built-up roofs employing bituminous materialsis that when there is an internal fire in the building, the temperaturescan be such as to cause the bituminous material to liquify and penetratethrough the deck into the interior, thereby feeding the fire and causinggreater fire damage, as well as greater hazard to fire personnelinvolved in fighting the fire. Accordingly, it is necessary to provide abarrier to such bituminous liquid from entering the building. In priorart built-up roofs, the half-inch fiber board is intended to prevent theoverlying bituminous material from passing through the base sheet andentering the building. However, the size and weight of the fiber boardprecludes the board from being laid down as one continuous sheet.Instead, the fiber board is in the form of plurality of blocks ofrelatively easy to handle dimensions which are laid down side by sidewith seams between adjacent blocks. As a result, there is a possibilityof bituminous liquid entering the building through such seams.

Because the panels 10 overlap there are no seams in a roof 20 formedusing the panels 10. Accordingly, any liquid bituminous material isprevented from passing through to any of the underlying layers. Thus,the present invention provides superior fire safety features as comparedto the prior art.

When the roof covering is a single ply membrane, such membranepreferably comprises an elasto/polymeric material. Without limitation onthe generality of useful materials, the membrane may be formed ofethylene propylene diene monomer (EPDM), modified bitumen (MB),reinforced modified bitumen (MB/R), polychloroprene or neoprene (NEO),polyvinyl chloride (PVC), chlorinated polyethylene (CPE),polyisobutylene (PIB), or ethylene-copolymer-bitumen and anthracitemicrodust (ECB). The adhesive is chosen for its compatibility with thematerial comprising the membrane.

The number of fasteners employed in securing the base sheet to anunderlying deck is a function of the hold down force required to achievea given wind uplift prevention. Factory Mutual (“FM”), an independenttesting agency, in addition to testing roofs for certain fire preventioncriteria, also tests roofs to determine whether they have a desired winduplift prevention. The tests employed by FM are designated with aparticular PSF (pounds per square foot) number (“FM number”). Most roofswhich are required to pass an FM wind uplift prevention test arerequired to achieve an FM number of 90 PSF. Additional wind upliftcapabilities are tested for in increments of 30 PSF (e.g., 120 PSF, 150PSF, etc.).

There is no predetermined criteria for determining either the number offasteners or the spacing therebetween required to achieve a particularwind uplift prevention. Accordingly, the number of and spacing betweenfasteners will vary from installation to installation and, in mostcases, will have no correlation to an FM number.

In accordance with one aspect of the present invention, the locations ofthe fasteners for each FM number (e.g., 90 PSF, 120 PSF, etc.) arepredetermined by, for example, empirical methods. Then, indiciarepresenting the empirically determined locations to achieve each FMnumber are marked on the top surface of the base sheet.

More specifically, referring to FIG. 5, there is shown a plan view of abase sheet panel 10 having a plurality of different types of indiciathereon, such as crosses (+), triangles (Δ) and circles (∘). Eachdifferent type of indicia represents a given FM wind number and thelocation of each on the base sheet represents the location in which afastener should be inserted to achieve such FM number. In the exampleshown in FIG. 5, the crosses (+) represent 90 PSF, the triangles (Δ) 120PSF and the circles (∘) 150 PSF. It will be noted that the spacingbetween the crosses (+) are greater than the spacing between thetriangles (Δ) which in turn are greater than the spacing between thecircles (∘). That is, the spacing between indicia representing a lowerFM psi number is greater than the spacing between indicia representing ahigher FM number because the lower the FM number the less the number offasteners required and the greater the spacing therebetween.

It should now be appreciated that the present invention provides anumber of advantages as compared to prior art roofs:

-   -   1. It prevents gassing of the insulating board when using        urethane, isocyanurate or any foam that utilizes gas in the        cell. It is well known in the industry that isocyanurate        insulation releases gas from the topside when hot coal tar or        hot asphalt is applied. This gassing causes blistering and        delamination of the roofing membrane and normally as recommended        by NRCA requires a board overly. The panels 10, do not requires        a board overlay and thus eliminate the cost of the labor and        cost of the board overlay.    -   2. The panels 10 prevent hot molten tar or asphalt flowing        between the joints of the insulation board 18 protecting        occupants from serious burns. In the case of new construction,        it prevents inside workers from being burned by dripping hot tar        or asphalt.    -   3. The composite laminate 10 of polyester and aluminum enables        the insulation to be secured to the deck utilizing 50% less        fasteners then insulating boards void of the composite. For        example, if insulation boards 18 void of the composite were        installed approximately 36 fasteners would be utilized per 100        sq. ft. to obtain a 90 PSF rating. This wind lift rating is        required to be in compliance with all building codes in the        United States. This reduction in fasteners means less holes in        the deck, 50% less fasteners plus 50% less labor for the        installation.    -   4. Insulation boards 18 for roofing tend to be brittle. The        lamination 12 of the composite reduces breakage during shipping        and installation resulting in lower costs.    -   5. The laminated composite 12 adds dimensional strength to the        insulation board 18. It is well known in the industry that        roofing insulation, especially foam type insulation lacks        dimensional stability.    -   6. When attaching fasteners through insulation, it is necessary        that all fasteners are installed at the top of metal decking,        i.e., in order to pass Factory Mutual or Global or UL uplift        regulations and to comply with test listings, all fasteners must        be the top of metal decking. When using a roll, it is virtually        impossible to locate the top of a corrugated steel decking. It        is relatively, easy to do so, however, when using the panels 10.    -   7. When the composite 12 is laminated to the insulation board 18        at the factory to form the panels, the task of installation is        made easier as the individual boards are laid individually and        fastened. In contrast, in the loose laid method, the wind is a        negative factor, blowing unfastened insulation and causing work        stoppage and damage to insulation boards.    -   8. The two most notable testing agents are Factory Mutual Global        and UL Labs. These agencies are an important function in testing        all kinds of roofing membranes and insulation. The tests        conducted that are of extreme importance are wind uplift,        interior fire, hail damage and weather ability. Panels in        accordance with the invention perform exceptionally well on        these tests.    -   9. Tests have proven that the panels will achieve 150 PSI which        means it will withstand winds of 160 MPH to 170 PH. The        calorimeter test tests a roof membranes' resistance to interior        fire, the aluminum laminate prevents the asphalt or tar that        melts and flows from entering the building and spreading        interior fire, the non-woven polyester has extreme toughness        that resists puncturing the membrane from hail stones.    -   10. The aluminum 14 also acts as a vapor retarder, preventing        interior moisture in the form of vapor, from entering under and        into the roof membrane which can cause blistering.    -   11. Since the laminated composite 12 laps the joints of the        adlacent foam boards 18, it prevents asphalt from flowing        through the joints and into the building feeding the fire from        within.    -   12. The covering of the seams of the insulation boards 18        prevents ridging of the roof covering, as well as allows the        installation to pass interior UL and FM interior fire test        (Calorimeter).    -   13. If the composite is installed with the aluminum side 14 up,        a superior facing is created on which to install a self-adhering        roof membrane

The present invention thus provides a system that substantially reducescatastrophic damage resulting from both wind and fire and does so atreduced costs.

Although the present invention has been described in relation toparticular embodiments thereof, many other variations and modificationsand other uses will become apparent to those skilled in the art. Forexample, the metal layer of the panel may have embossments to provideventing, as disclosed in U.S. Pat. Nos. 6,108,993 and 5,884,446. It ispreferred, therefore, that the present invention be limited not by thespecific disclosure herein, but only by the appended claims.

1. A roofing panel comprising: an insulation board having aquadrilateral shape defining four edges; and a laminate of a metal layerand a fabric layer attached to said board such that said laminateoverhangs at least two of the edges of said boardfabric layer faces saiddeck.
 2. The roofing panel of claim 1, wherein the fabric of said fabriclayer is made of plastic.
 3. The roofing panel of claim 2, wherein saidplastic is non-woven polyester.
 4. The roofing panel of claim 1, whereinthe metal of said metal layer is aluminum.
 5. The roofing panel of claim1, wherein the metal layer is aluminum and the fabric layer is non-wovenpolyester.
 6. The roofing panel of claim 1, wherein the laminate isattached to the board with the metal layer in contact with the board. 7.The roofing panel of claim 1, wherein the laminate is attached to theboard with the fabric layer in contact with the board.
 8. A roofcomprising a plurality of roofing panels, each of the roofing panelscomprising an insulation board having a quadrilateral shape definingfour edges and a laminate of a metal layer and a fabric layer attachedto said board such that said laminate overhangs two of the edges of saidboard, thereby forming a roofing panel having two overhanging edges andtwo non- overhanging edges, the roofing panels being interconnected withone another such that an overhanging edge of one roofing panel overliesa non-overhanging edge of an adjacent roofing panel.
 9. The roof ofclaim 8, wherein the fabric of said fabric layer is made of plastic. 10.The roof of claim 9, wherein said plastic is non-woven polyester. 11.The roof of claim 8, wherein the metal of said metal layer is aluminum.12. The roof of claim 8, wherein the metal layer is aluminum and thefabric layer is non-woven polyester.
 13. The roof of claim 8, whereinthe laminate is attached to the board with the metal layer in contactwith the board.
 14. The roof of claim 8, wherein the laminate isattached to the board with the fabric layer in contact with the board.15. A method of forming a roof on a deck comprising: placing a pluralityof roofing panels over said deck, each of the roofing panels comprisingan insulation board having a quadrilateral shape defining four edges anda laminate of a metal layer and a fabric layer attached to said boardsuch that said laminate overhangs two of the edges of said board,thereby forming a roofing panel having two overhanging edges and twonon- overhanging edges, the roofing panels being interconnected with oneanother such that an overhanging edge of one roofing panel overlies anon-overhanging edge of an adjacent roofing panel. an insulating layerover said deck; and fastening said panels to said deck.
 16. The methodof claim 15, wherein the fabric of said fabric layer is made of plastic.17. The method of claim 16, wherein said plastic is non-woven polyester.18. The method of claim 15, wherein the metal of said metal layer isaluminum.
 19. The method of claim 15, wherein the metal layer isaluminum and the fabric layer is non-woven polyester.
 20. The method ofclaim 15, wherein the laminate is attached to the board with the metallayer in contact with the board.
 21. The method of claim 15, wherein thelaminate is attached to the board with the fabric layer in contact withthe board.
 22. The method of claim 15, further comprising applying abuilt-up roof composite over said laminate.
 23. The method of claim 15,further comprising applying a single-ply membrane over said laminate.24. The method of claim 15, wherein the layer of each panel on the sidefacing away from the deck has a plurality of different types of indicia,each type of indicia representing a different wind uplift prevention,and wherein the step of fastening said panels to said deck includesinserting fasteners through said panels at locations corresponding tothe location of the types of indicia representing a desired wind upliftprevention.